[PATCH] switchdev: add Kconfig dependencies for bridge

[PATCH] switchdev: add Kconfig dependencies for bridge

[Arnd Bergmann]

From: Arnd Bergmann <arnd@arndb.de>

Multiple switchdev drivers depend on CONFIG_NET_SWITCHDEV in Kconfig,
but have also gained a dependency on the bridge driver as they now
call switchdev_bridge_port_offload():

drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.o: In function `sparx5_netdevice_event':
sparx5_switchdev.c:(.text+0x3cc): undefined reference to `switchdev_bridge_port_offload'
drivers/net/ethernet/ti/cpsw_new.o: In function `cpsw_netdevice_event':
cpsw_new.c:(.text+0x1098): undefined reference to `switchdev_bridge_port_offload'

Some of these drivers already have a 'BRIDGE || !BRIDGE' dependency
that avoids the link failure, but the 'rocker' driver was missing this

For MLXSW/MLX5, SPARX5_SWITCH, and TI_K3_AM65_CPSW_NUSS, the
driver can conditionally use switchdev support, which is then guarded
by another Kconfig symbol. For these, add a dependency on a new Kconfig
symbol NET_MAY_USE_SWITCHDEV that is defined to correctly model the
dependency: if switchdev support is enabled, these drivers cannot be
built-in when bridge support is in a module, but if either bridge or
switchdev is disabled, or both are built-in, there is no such restriction.

Fixes: 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded")
Fixes: b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module")
Signed-off-by: Arnd Bergmann <arnd@arndb.de>
---
This version seems to pass my randconfig builds for the moment,
but that doesn't mean it's correct either. Please have a closer
look before this gets applied.
---
 drivers/net/ethernet/mellanox/mlx5/core/Kconfig | 1 +
 drivers/net/ethernet/mellanox/mlxsw/Kconfig     | 1 +
 drivers/net/ethernet/netronome/Kconfig          | 1 +
 drivers/net/ethernet/ti/Kconfig                 | 1 +
 net/switchdev/Kconfig                           | 5 +++++
 5 files changed, 9 insertions(+)

diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
index e1a5a79e27c7..3a752e57c1e5 100644
--- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
@@ -12,6 +12,7 @@ config MLX5_CORE
 	depends on MLXFW || !MLXFW
 	depends on PTP_1588_CLOCK || !PTP_1588_CLOCK
 	depends on PCI_HYPERV_INTERFACE || !PCI_HYPERV_INTERFACE
+	depends on NET_MAY_USE_SWITCHDEV
 	help
 	  Core driver for low level functionality of the ConnectX-4 and
 	  Connect-IB cards by Mellanox Technologies.
diff --git a/drivers/net/ethernet/mellanox/mlxsw/Kconfig b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
index 12871c8dc7c1..dee3925bdaea 100644
--- a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
@@ -5,6 +5,7 @@
 
 config MLXSW_CORE
 	tristate "Mellanox Technologies Switch ASICs support"
+	depends on NET_MAY_USE_SWITCHDEV
 	select NET_DEVLINK
 	select MLXFW
 	help
diff --git a/drivers/net/ethernet/netronome/Kconfig b/drivers/net/ethernet/netronome/Kconfig
index b82758d5beed..a298d19e8383 100644
--- a/drivers/net/ethernet/netronome/Kconfig
+++ b/drivers/net/ethernet/netronome/Kconfig
@@ -21,6 +21,7 @@ config NFP
 	depends on PCI && PCI_MSI
 	depends on VXLAN || VXLAN=n
 	depends on TLS && TLS_DEVICE || TLS_DEVICE=n
+	depends on NET_MAY_USE_SWITCHDEV
 	select NET_DEVLINK
 	select CRC32
 	help
diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
index 07192613256e..a73c6c236b25 100644
--- a/drivers/net/ethernet/ti/Kconfig
+++ b/drivers/net/ethernet/ti/Kconfig
@@ -93,6 +93,7 @@ config TI_CPTS
 config TI_K3_AM65_CPSW_NUSS
 	tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
 	depends on OF && TI_K3_UDMA_GLUE_LAYER
+	depends on NET_MAY_USE_SWITCHDEV
 	select NET_DEVLINK
 	select TI_DAVINCI_MDIO
 	imply PHY_TI_GMII_SEL
diff --git a/net/switchdev/Kconfig b/net/switchdev/Kconfig
index 18a2d980e11d..3b0e627a4519 100644
--- a/net/switchdev/Kconfig
+++ b/net/switchdev/Kconfig
@@ -12,3 +12,8 @@ config NET_SWITCHDEV
 	  meaning of the word "switch". This include devices supporting L2/L3 but
 	  also various flow offloading chips, including switches embedded into
 	  SR-IOV NICs.
+
+config NET_MAY_USE_SWITCHDEV
+	def_tristate y
+	depends on NET_SWITCHDEV || NET_SWITCHDEV=n
+	depends on BRIDGE || NET_SWITCHDEV=n
-- 
2.29.2

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Simon Horman]

On Mon, Aug 02, 2021 at 04:47:28PM +0200, Arnd Bergmann wrote:
> From: Arnd Bergmann <arnd@arndb.de>
> 
> Multiple switchdev drivers depend on CONFIG_NET_SWITCHDEV in Kconfig,
> but have also gained a dependency on the bridge driver as they now
> call switchdev_bridge_port_offload():
> 
> drivers/net/ethernet/microchip/sparx5/sparx5_switchdev.o: In function `sparx5_netdevice_event':
> sparx5_switchdev.c:(.text+0x3cc): undefined reference to `switchdev_bridge_port_offload'
> drivers/net/ethernet/ti/cpsw_new.o: In function `cpsw_netdevice_event':
> cpsw_new.c:(.text+0x1098): undefined reference to `switchdev_bridge_port_offload'
> 
> Some of these drivers already have a 'BRIDGE || !BRIDGE' dependency
> that avoids the link failure, but the 'rocker' driver was missing this
> 
> For MLXSW/MLX5, SPARX5_SWITCH, and TI_K3_AM65_CPSW_NUSS, the
> driver can conditionally use switchdev support, which is then guarded
> by another Kconfig symbol. For these, add a dependency on a new Kconfig
> symbol NET_MAY_USE_SWITCHDEV that is defined to correctly model the
> dependency: if switchdev support is enabled, these drivers cannot be
> built-in when bridge support is in a module, but if either bridge or
> switchdev is disabled, or both are built-in, there is no such restriction.
> 
> Fixes: 2f5dc00f7a3e ("net: bridge: switchdev: let drivers inform which bridge ports are offloaded")
> Fixes: b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module")
> Signed-off-by: Arnd Bergmann <arnd@arndb.de>
> ---
> This version seems to pass my randconfig builds for the moment,
> but that doesn't mean it's correct either. Please have a closer
> look before this gets applied.
> ---
>  drivers/net/ethernet/mellanox/mlx5/core/Kconfig | 1 +
>  drivers/net/ethernet/mellanox/mlxsw/Kconfig     | 1 +
>  drivers/net/ethernet/netronome/Kconfig          | 1 +
>  drivers/net/ethernet/ti/Kconfig                 | 1 +
>  net/switchdev/Kconfig                           | 5 +++++
>  5 files changed, 9 insertions(+)
> 
> diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> index e1a5a79e27c7..3a752e57c1e5 100644
> --- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> +++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> @@ -12,6 +12,7 @@ config MLX5_CORE
>  	depends on MLXFW || !MLXFW
>  	depends on PTP_1588_CLOCK || !PTP_1588_CLOCK
>  	depends on PCI_HYPERV_INTERFACE || !PCI_HYPERV_INTERFACE
> +	depends on NET_MAY_USE_SWITCHDEV
>  	help
>  	  Core driver for low level functionality of the ConnectX-4 and
>  	  Connect-IB cards by Mellanox Technologies.

MLX5_CORE does not appear to cover code that calls
switchdev_bridge_port_offload.

> diff --git a/drivers/net/ethernet/mellanox/mlxsw/Kconfig b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> index 12871c8dc7c1..dee3925bdaea 100644
> --- a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> +++ b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> @@ -5,6 +5,7 @@
>  
>  config MLXSW_CORE
>  	tristate "Mellanox Technologies Switch ASICs support"
> +	depends on NET_MAY_USE_SWITCHDEV
>  	select NET_DEVLINK
>  	select MLXFW
>  	help

I think it is MLXSW_SPECTRUM rather than MLXSW_CORE
that controls compilation of spectrum_switchdev.c
which calls switchdev_bridge_port_offload.

But MLXSW_SPECTRUM seems to already depend on BRIDGE || BRIDGE=n

> diff --git a/drivers/net/ethernet/netronome/Kconfig b/drivers/net/ethernet/netronome/Kconfig
> index b82758d5beed..a298d19e8383 100644
> --- a/drivers/net/ethernet/netronome/Kconfig
> +++ b/drivers/net/ethernet/netronome/Kconfig
> @@ -21,6 +21,7 @@ config NFP
>  	depends on PCI && PCI_MSI
>  	depends on VXLAN || VXLAN=n
>  	depends on TLS && TLS_DEVICE || TLS_DEVICE=n
> +	depends on NET_MAY_USE_SWITCHDEV
>  	select NET_DEVLINK
>  	select CRC32
>  	help

This seems wrong, the NFP driver doesn't call
switchdev_bridge_port_offload()

> diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> index 07192613256e..a73c6c236b25 100644
> --- a/drivers/net/ethernet/ti/Kconfig
> +++ b/drivers/net/ethernet/ti/Kconfig
> @@ -93,6 +93,7 @@ config TI_CPTS
>  config TI_K3_AM65_CPSW_NUSS
>  	tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
>  	depends on OF && TI_K3_UDMA_GLUE_LAYER
> +	depends on NET_MAY_USE_SWITCHDEV
>  	select NET_DEVLINK
>  	select TI_DAVINCI_MDIO
>  	imply PHY_TI_GMII_SEL

I believe this has already been addressed by the following patch in net

b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module")

> diff --git a/net/switchdev/Kconfig b/net/switchdev/Kconfig
> index 18a2d980e11d..3b0e627a4519 100644
> --- a/net/switchdev/Kconfig
> +++ b/net/switchdev/Kconfig
> @@ -12,3 +12,8 @@ config NET_SWITCHDEV
>  	  meaning of the word "switch". This include devices supporting L2/L3 but
>  	  also various flow offloading chips, including switches embedded into
>  	  SR-IOV NICs.
> +
> +config NET_MAY_USE_SWITCHDEV
> +	def_tristate y
> +	depends on NET_SWITCHDEV || NET_SWITCHDEV=n
> +	depends on BRIDGE || NET_SWITCHDEV=n
> -- 
> 2.29.2
> 

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Arnd Bergmann]

On Mon, Aug 2, 2021 at 6:23 PM Simon Horman <simon.horman@corigine.com> wrote:
> On Mon, Aug 02, 2021 at 04:47:28PM +0200, Arnd Bergmann wrote:
> > ---
> > This version seems to pass my randconfig builds for the moment,
> > but that doesn't mean it's correct either. Please have a closer
> > look before this gets applied.

Thank you for taking a look, it seems I have done a particularly bad
job rebasing
the patch on top of the previous fix, leaving only the wrong bits ;-)

> > diff --git a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> > index e1a5a79e27c7..3a752e57c1e5 100644
> > --- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> > +++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
> > @@ -12,6 +12,7 @@ config MLX5_CORE
> >       depends on MLXFW || !MLXFW
> >       depends on PTP_1588_CLOCK || !PTP_1588_CLOCK
> >       depends on PCI_HYPERV_INTERFACE || !PCI_HYPERV_INTERFACE
> > +     depends on NET_MAY_USE_SWITCHDEV
> >       help
> >         Core driver for low level functionality of the ConnectX-4 and
> >         Connect-IB cards by Mellanox Technologies.
>
> MLX5_CORE does not appear to cover code that calls
> switchdev_bridge_port_offload.

Ah right, I did get a link failure with my test build, but it was an
unrelated one:

ld: drivers/net/ethernet/mellanox/mlx5/core/esw/sample.o: in function
`mlx5_esw_sample_skb':
sample.c:(.text+0x5b4): undefined reference to `psample_sample_packet'

I think that one needs

--- a/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
+++ b/drivers/net/ethernet/mellanox/mlx5/core/Kconfig
@@ -90,6 +90,7 @@ config MLX5_BRIDGE
 config MLX5_CLS_ACT
        bool "MLX5 TC classifier action support"
        depends on MLX5_ESWITCH && NET_CLS_ACT
+       depends on PSAMPLE=y || PSAMPLE=MLX5_CORE
        default y
        help
          mlx5 ConnectX offloads support for TC classifier action (NET_CLS_ACT),

but this is unrelated and I have not tested that.

> > diff --git a/drivers/net/ethernet/mellanox/mlxsw/Kconfig b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> > index 12871c8dc7c1..dee3925bdaea 100644
> > --- a/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> > +++ b/drivers/net/ethernet/mellanox/mlxsw/Kconfig
> > @@ -5,6 +5,7 @@
> >
> >  config MLXSW_CORE
> >       tristate "Mellanox Technologies Switch ASICs support"
> > +     depends on NET_MAY_USE_SWITCHDEV
> >       select NET_DEVLINK
> >       select MLXFW
> >       help
>
> I think it is MLXSW_SPECTRUM rather than MLXSW_CORE
> that controls compilation of spectrum_switchdev.c
> which calls switchdev_bridge_port_offload.
>
> But MLXSW_SPECTRUM seems to already depend on BRIDGE || BRIDGE=n

Ok.

> > diff --git a/drivers/net/ethernet/netronome/Kconfig b/drivers/net/ethernet/netronome/Kconfig
> > index b82758d5beed..a298d19e8383 100644
> > --- a/drivers/net/ethernet/netronome/Kconfig
> > +++ b/drivers/net/ethernet/netronome/Kconfig
> > @@ -21,6 +21,7 @@ config NFP
> >       depends on PCI && PCI_MSI
> >       depends on VXLAN || VXLAN=n
> >       depends on TLS && TLS_DEVICE || TLS_DEVICE=n
> > +     depends on NET_MAY_USE_SWITCHDEV
> >       select NET_DEVLINK
> >       select CRC32
> >       help
>
> This seems wrong, the NFP driver doesn't call
> switchdev_bridge_port_offload()

Ah right, I actually noticed that earlier and then forgot to remove that hunk.

Also: is this actually intended or should the driver call
switchdev_bridge_port_offload() like the other switchdev drivers do?

> > diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> > index 07192613256e..a73c6c236b25 100644
> > --- a/drivers/net/ethernet/ti/Kconfig
> > +++ b/drivers/net/ethernet/ti/Kconfig
> > @@ -93,6 +93,7 @@ config TI_CPTS
> >  config TI_K3_AM65_CPSW_NUSS
> >       tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
> >       depends on OF && TI_K3_UDMA_GLUE_LAYER
> > +     depends on NET_MAY_USE_SWITCHDEV
> >       select NET_DEVLINK
> >       select TI_DAVINCI_MDIO
> >       imply PHY_TI_GMII_SEL
>
> I believe this has already been addressed by the following patch in net
>
> b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module")

I think the fix was wrong here, and that hunk should be reverted.
The dependency was added to a bool option, where it does not have
the intended effect.

I think this is the only remaining thing needed from my patch, so
the NET_MAY_USE_SWITCHDEV option is not needed either,
and it could be written as:

diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
index 07192613256e..e49006a96d49 100644
--- a/drivers/net/ethernet/ti/Kconfig
+++ b/drivers/net/ethernet/ti/Kconfig
@@ -93,6 +93,7 @@ config TI_CPTS
 config TI_K3_AM65_CPSW_NUSS
        tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
        depends on OF && TI_K3_UDMA_GLUE_LAYER
+       depends on (BRIDGE && NET_SWITCHDEV) || BRIDGE=n || NET_SWITCHDEV=n
        select NET_DEVLINK
        select TI_DAVINCI_MDIO
        imply PHY_TI_GMII_SEL
@@ -110,7 +111,6 @@ config TI_K3_AM65_CPSW_NUSS
 config TI_K3_AM65_CPSW_SWITCHDEV
        bool "TI K3 AM654x/J721E CPSW Switch mode support"
        depends on TI_K3_AM65_CPSW_NUSS
-       depends on BRIDGE || BRIDGE=n
        depends on NET_SWITCHDEV
        help
         This enables switchdev support for TI K3 CPSWxG Ethernet

If this looks correct to you, I can submit it as a standalone patch.

      Arnd

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Simon Horman]

On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> On Mon, Aug 2, 2021 at 6:23 PM Simon Horman <simon.horman@corigine.com> wrote:
> > On Mon, Aug 02, 2021 at 04:47:28PM +0200, Arnd Bergmann wrote:
> > > ---
> > > This version seems to pass my randconfig builds for the moment,
> > > but that doesn't mean it's correct either. Please have a closer
> > > look before this gets applied.
> 
> Thank you for taking a look, it seems I have done a particularly bad
> job rebasing
> the patch on top of the previous fix, leaving only the wrong bits ;-)

:)

...

> > > diff --git a/drivers/net/ethernet/netronome/Kconfig b/drivers/net/ethernet/netronome/Kconfig
> > > index b82758d5beed..a298d19e8383 100644
> > > --- a/drivers/net/ethernet/netronome/Kconfig
> > > +++ b/drivers/net/ethernet/netronome/Kconfig
> > > @@ -21,6 +21,7 @@ config NFP
> > >       depends on PCI && PCI_MSI
> > >       depends on VXLAN || VXLAN=n
> > >       depends on TLS && TLS_DEVICE || TLS_DEVICE=n
> > > +     depends on NET_MAY_USE_SWITCHDEV
> > >       select NET_DEVLINK
> > >       select CRC32
> > >       help
> >
> > This seems wrong, the NFP driver doesn't call
> > switchdev_bridge_port_offload()
> 
> Ah right, I actually noticed that earlier and then forgot to remove that hunk.
> 
> Also: is this actually intended or should the driver call
> switchdev_bridge_port_offload() like the other switchdev drivers do?

The NFP driver doesn't implement /use this part of the switchdev API.
It is intentional given the current scope of features implemented.

> > > diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> > > index 07192613256e..a73c6c236b25 100644
> > > --- a/drivers/net/ethernet/ti/Kconfig
> > > +++ b/drivers/net/ethernet/ti/Kconfig
> > > @@ -93,6 +93,7 @@ config TI_CPTS
> > >  config TI_K3_AM65_CPSW_NUSS
> > >       tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
> > >       depends on OF && TI_K3_UDMA_GLUE_LAYER
> > > +     depends on NET_MAY_USE_SWITCHDEV
> > >       select NET_DEVLINK
> > >       select TI_DAVINCI_MDIO
> > >       imply PHY_TI_GMII_SEL
> >
> > I believe this has already been addressed by the following patch in net
> >
> > b0e81817629a ("net: build all switchdev drivers as modules when the bridge is a module")
> 
> I think the fix was wrong here, and that hunk should be reverted.
> The dependency was added to a bool option, where it does not have
> the intended effect.
> 
> I think this is the only remaining thing needed from my patch, so
> the NET_MAY_USE_SWITCHDEV option is not needed either,
> and it could be written as:
> 
> diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
> index 07192613256e..e49006a96d49 100644
> --- a/drivers/net/ethernet/ti/Kconfig
> +++ b/drivers/net/ethernet/ti/Kconfig
> @@ -93,6 +93,7 @@ config TI_CPTS
>  config TI_K3_AM65_CPSW_NUSS
>         tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
>         depends on OF && TI_K3_UDMA_GLUE_LAYER
> +       depends on (BRIDGE && NET_SWITCHDEV) || BRIDGE=n || NET_SWITCHDEV=n
>         select NET_DEVLINK
>         select TI_DAVINCI_MDIO
>         imply PHY_TI_GMII_SEL
> @@ -110,7 +111,6 @@ config TI_K3_AM65_CPSW_NUSS
>  config TI_K3_AM65_CPSW_SWITCHDEV
>         bool "TI K3 AM654x/J721E CPSW Switch mode support"
>         depends on TI_K3_AM65_CPSW_NUSS
> -       depends on BRIDGE || BRIDGE=n
>         depends on NET_SWITCHDEV
>         help
>          This enables switchdev support for TI K3 CPSWxG Ethernet
> 
> If this looks correct to you, I can submit it as a standalone patch.

Is there a conflict between your proposed change and the
presence of "depends on NET_SWITCHDEV" ?

BTW, I'm not sure I know how to compile TI_K3_AM65_CPSW_NUSS.
So I'm perhaps not the best arbiter of correctness here.

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Vladimir Oltean]

On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> If this looks correct to you, I can submit it as a standalone patch.

I think it's easiest I just ask you to provide a .config that triggers
actual build failures and we can go from there.

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Arnd Bergmann]

On Mon, Aug 2, 2021 at 9:05 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
>
> On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> > If this looks correct to you, I can submit it as a standalone patch.
>
> I think it's easiest I just ask you to provide a .config that triggers
> actual build failures and we can go from there.

This one is with an arm64 allmodconfig, plus

CONFIG_PTP_1588_CLOCK=y
CONFIG_TI_K3_AM65_CPTS=y
CONFIG_TI_K3_AM65_CPSW_NUSS=y

       Arnd

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Vladimir Oltean]

On Mon, Aug 02, 2021 at 09:55:20PM +0200, Arnd Bergmann wrote:
> On Mon, Aug 2, 2021 at 9:05 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
> >
> > On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> > > If this looks correct to you, I can submit it as a standalone patch.
> >
> > I think it's easiest I just ask you to provide a .config that triggers
> > actual build failures and we can go from there.
> 
> This one is with an arm64 allmodconfig, plus
> 
> CONFIG_PTP_1588_CLOCK=y
> CONFIG_TI_K3_AM65_CPTS=y
> CONFIG_TI_K3_AM65_CPSW_NUSS=y

Yeah, ok, I remember now, I saw that TI_CPSW_SWITCHDEV is tristate, and
incorrectly thought that TI_K3_AM65_CPSW_SWITCHDEV (which is mostly a
copy-paste job of the main cpsw anyway, makes you cringe that they wrote
a separate driver for it) is tristate too.

The options are either to make TI_K3_AM65_CPSW_SWITCHDEV tristate like
TI_CPSW_SWITCHDEV is, and to edit the Makefile accordingly to make
am65-cpsw-switchdev.o part of obj-$(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV),
or to extend the BRIDGE || BRIDGE=n dependency to TI_K3_AM65_CPSW_NUSS
which is the direct tristate dependency of CONFIG_TI_K3_AM65_CPSW_SWITCHDEV,
and to make CONFIG_TI_K3_AM65_CPSW_SWITCHDEV simply depend on BRIDGE.

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Arnd Bergmann]

On Mon, Aug 2, 2021 at 10:21 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
>
> On Mon, Aug 02, 2021 at 09:55:20PM +0200, Arnd Bergmann wrote:
> > On Mon, Aug 2, 2021 at 9:05 PM Vladimir Oltean <vladimir.oltean@nxp.com> wrote:
> > >
> > > On Mon, Aug 02, 2021 at 08:29:25PM +0200, Arnd Bergmann wrote:
> > > > If this looks correct to you, I can submit it as a standalone patch.
> > >
> > > I think it's easiest I just ask you to provide a .config that triggers
> > > actual build failures and we can go from there.
> >
> > This one is with an arm64 allmodconfig, plus
> >
> > CONFIG_PTP_1588_CLOCK=y
> > CONFIG_TI_K3_AM65_CPTS=y
> > CONFIG_TI_K3_AM65_CPSW_NUSS=y
>
> Yeah, ok, I remember now, I saw that TI_CPSW_SWITCHDEV is tristate, and
> incorrectly thought that TI_K3_AM65_CPSW_SWITCHDEV (which is mostly a
> copy-paste job of the main cpsw anyway, makes you cringe that they wrote
> a separate driver for it) is tristate too.

Right.

> The options are either to make TI_K3_AM65_CPSW_SWITCHDEV tristate like
> TI_CPSW_SWITCHDEV is, and to edit the Makefile accordingly to make
> am65-cpsw-switchdev.o part of obj-$(CONFIG_TI_K3_AM65_CPSW_SWITCHDEV),

This probably won't work as this is currently part of the ti-am65-cpsw-nuss.ko
module, so I would assume that it's not easy to separate from the main module.

> or to extend the BRIDGE || BRIDGE=n dependency to TI_K3_AM65_CPSW_NUSS
> which is the direct tristate dependency of CONFIG_TI_K3_AM65_CPSW_SWITCHDEV,

That would work, but it's slightly more heavy-handed than my proposal, as this
prevents TI_K3_AM65_CPSW_NUSS from being built-in when BRIDGE is a module,
even when switchdev support is completely disabled.

> and to make CONFIG_TI_K3_AM65_CPSW_SWITCHDEV simply depend on BRIDGE.

This would not be needed then I think.

       Arnd

Re: [PATCH] switchdev: add Kconfig dependencies for bridge

[Vladimir Oltean]

On Mon, Aug 02, 2021 at 10:44:04PM +0200, Arnd Bergmann wrote:
> > or to extend the BRIDGE || BRIDGE=n dependency to TI_K3_AM65_CPSW_NUSS
> > which is the direct tristate dependency of CONFIG_TI_K3_AM65_CPSW_SWITCHDEV,
> 
> That would work, but it's slightly more heavy-handed than my proposal, as this
> prevents TI_K3_AM65_CPSW_NUSS from being built-in when BRIDGE is a module,
> even when switchdev support is completely disabled.
> 
> > and to make CONFIG_TI_K3_AM65_CPSW_SWITCHDEV simply depend on BRIDGE.
> 
> This would not be needed then I think.

I've tested this change according to your suggestion:

diff --git a/drivers/net/ethernet/ti/Kconfig b/drivers/net/ethernet/ti/Kconfig
index 7ac8e5ecbe97..a9980cfc504b 100644
--- a/drivers/net/ethernet/ti/Kconfig
+++ b/drivers/net/ethernet/ti/Kconfig
@@ -93,6 +93,7 @@ config TI_CPTS
 config TI_K3_AM65_CPSW_NUSS
 	tristate "TI K3 AM654x/J721E CPSW Ethernet driver"
 	depends on ARCH_K3 && OF && TI_K3_UDMA_GLUE_LAYER
+	depends on (BRIDGE && NET_SWITCHDEV) || BRIDGE=n || NET_SWITCHDEV=n
 	select NET_DEVLINK
 	select TI_DAVINCI_MDIO
 	imply PHY_TI_GMII_SEL
(1/2) Stage this hunk [y,n,q,a,d,j,J,g,/,e,?]? y
@@ -110,7 +111,6 @@ config TI_K3_AM65_CPSW_NUSS
 config TI_K3_AM65_CPSW_SWITCHDEV
 	bool "TI K3 AM654x/J721E CPSW Switch mode support"
 	depends on TI_K3_AM65_CPSW_NUSS
-	depends on BRIDGE || BRIDGE=n
 	depends on NET_SWITCHDEV
 	help
 	 This enables switchdev support for TI K3 CPSWxG Ethernet

and it does appear to work, so when you resubmit please feel free to add:

Reviewed-by: Vladimir Oltean <vladimir.oltean@nxp.com>
Tested-by: Vladimir Oltean <vladimir.oltean@nxp.com>

Thanks and sorry for breaking the dependency chain yet again! It takes
time to learn this stuff.